Block-signaling system.



No. 794,784. PATBNTED JULY 18, 1905.

K H. M. GOULTBR. v

BLOCK SIGNALING SYSTEM.

APPLIOATIOH FILED SEPT. 5. 1903.

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PATENTED JULY 18, 1905.

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M 00., LITHOGRAVHERS. wAsHmaYoN n c Patented July 18, 1905.

PATENT OFFICE.

HARRY M. COULTER, OF CHICAGO, ILLINOIS.

BLOCK-SIGNALING SYSTEM.

SPECIFICATION forming part of Letters Patent No. 794,784, dated July 18, 1905.

Applicatipnfiled September 5, 1903. Serial No. 172,032.

To all lull/0771 it Duty concern:

Be it known thatI, HARRY M. COULTER, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a certain new and useful Improvement in Block-Signaling Systems, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

My invention relates to railway block-signaling systems, and more particularly to that class of block-signaling systems in which the signals are sounded or displayed in the enginecab or upon the moving train rather than as visual signals at the side of a railroad-track.

There have heretofore been many attempts to provide a cab signaling system; but, so far as I am aware, none of these systems have proven satisfactory in operation. Without going to the length of enumerating the defects of these systems of the prior art I may call attention to the advantages which the system of my invention provides over those of the prior art. A block-signaling system constructed in accordance with my invention may be used on a single-track railroad to provide block-signals in both directions that is, blocksignals are provided for a following train no matter in which direction the two trains are moving, and, furthermore, a block-signal is provided in the case of two trains meeting head to head.

A system constructed in accordance with my invention provides a double block-that is, there are produced both caution and deadstop signals. This feature is particularly useful in the case of two trains, one following the other, whether used in connection with a single-track or a double-track railroad. My invention provides a system in which there shall be absolute protection at every point and under all conditions as distinguished from certain systems of the prior art in which certain peculiar conditions may arise at rare intervals at which the proper signals are not produced.

There is provided in connection with my invention means whereby a test-circuit serves to indicate at all times to the engineer or other trainman whether or not the block-signaling system is in perfect operative condition, such that it may be relied upon for signaling purposes.

A further advantage due to the installation of my block-signaling system consists in the fabt that while certain of the rolling-stock or engines may be provided with apparatus to provide signals in accordance with my invention it is unnecessary that all of the engines or rolling-stock be similarly equipped, and in case any engine is provided with the signaling apparatus this apparatus will be actuated in conjunction with other rolling-stock which is not similarly equipped.

My invention provides a system in which a normally closed track-circuit is employed and in connection with this closed circuit there is provided means whereby any derangement of the track-circuit, either in the nature of a broken circuit or a short circuit, will be indicated at once by a display or actuation of the danger-signal, and if any part of the signalcircuit is deranged, either by short circuit, ground, or broken wires, it will be indicated by the test-signal.

My system presents the further advantage that its proper operation does not depend upon the proper working of any one relay or one set of battery or source of current or one trackcircuit; but there is the advantage of duplicate sets, at least one of which is sure to be in operative condition.

In addition to these advantages, which are peculiar to the system of my own invention, there are of course all of the well-known advantages of cab signaling systems over sys tems in which stationary signals at the side of the railroad-track are employed.

I shall describe my invention by reference to the accompanying drawings, in which- Figure 1 diagrammatically illustrates the track arrangement and circuit connections of the preferred embodiment of my invention.

Fig. 2 diagrammatically illustrates the circuit arrangements provided upon an engine-cab or other part of a train. Fig. 3 diagrammatically represents a switching device which may be associated with the reverse-lever of the engine. and Fig. 4c diagrammatically illustrates a modified circuit arrangement partic- "ularly adapted for use where long blocks are employed. 1 In Fig. 1 I have diagrammatically illustrated a portion of a single-track railway divided into blocks numbered 11, 12, 13, 14, and 15, it being understood,'of course, that any number of blocks may be employed. In each of the blocks the two main rails a and Z) are insulated so far as possible from the ground and from each other. At some suitable point in each block these two rails are connected by a conductor 0, there being included in this conductor a battery d or other suitable source of current, together with a resistance 6, this resistance being solely for the purpose of preventing a dead shortcircuit of the source of current (Z, as will hereinafter more fully ap pear. .In each block there is provided-a plurality of grounded contact-rails f f. If the system is to be employed in connection with a double-track railroad in which trains are moved upon either track in only one direction, there is provided at one side of the track and for each block a series of insulated contact-rails g g. If a single track is used for trains moving in both directions, a second set of insulated.contact-rails [L h is desirably pro vided for each block. Each block, furthermore, is provided with a track-relay i, this relay being connected, as shown, between the two main rails a and bof its own block. This relay by means of one or more armatures, as

j and 7c, serves to control various electrical circuits,to be hereinafter more fully described.

Taking, for example, the relay 6, provided for block 13, it will be seen that under normal conditions when no car or engine-truck is upon the block 13 a circuit may be traced from the battery 01 for block 13 through the rail or, the relay 2', rail I), resistance a, and conductor 0 back to the other pole of the battery or source of current d. Current passing through this circuit causes an energization of the relay?) suflicient to maintain the armatures j and 7c in their attracted positions, as shown in thefull lines. Under this condition it will be seen that the electrical connection of the armature in with its back contacts Z and m is broken. The armature however, makes connection with the front contact a, thereby connecting the low-voltage battery 0 between the ground G and the insulated contacts 9 g of block 11, this connection being through a resistance-coil At the same time'the positive pole of the battery 0' is connected,through the resistance q, with the insulated contactrails 71/ h of block 15. In the same manner the relay z' of block 1 1 normally connects the positive pole of the associated low-voltage battery 0' with the contact+rails g g of the second block to the left, which is numbered 12, and through the associated resistance (1 with the insulated contacts h h of the second block to the right. Thus under normal conditions all of the relays i of all the blocks are energiZed to hold their armatures in their attracted positions. This connects the positive .pole of each of the low-voltage batteries 0 with the insulated contact-rails two blocks to the rear and two blocks in advance. As will hereinafter be more fully explained, the current from this low-voltage battery 0 is used solely for the purpose of operating the test system intended to indicate to the engineer that the signaling system is in proper operative condition and may be entirely depended and relied upon.

In case the truck of an engine or car of any kind is upon any one of the blocksfor instance, block l3-the wheels and axle will close a circuit between the rails a, and b in shunt of the relay i. The circuit closed by a truck in this manner is of extremely low resistance, and the associated relay 6 is shunted or short-circuited, the circuit from the associated battery (Z being now traced through the rail (0, the truck upon the block 13, rail 6, resistance e, and conductor 0 to the other pole of the battery (Z. The current flowing through the relay 2' is in this manner almost'wholly cut off, whereby the relay 7 is deenergized to permit the retraction of its armatures j and 70. The retraction of the armature j causes its electrical connection with the back contact r, whereby the following circuits may be traced: from ground Gr through the high-voltage battery 8, back contact 9', armature 7, resistance p, and thence to the insulated contact-rails g g of block 11. At the same time the positive pole of battery 8 is connected, through the resistance q, with the insulated contact-rails [L h of block 15. Thus the high-voltage source of current 8 is connected, through a suitable resistance p or q, as the case may be, with the insulated contact-rails two blocks distant in both directions. It will be noted that the insulated contact-rails which are thus connected to the rear of a train on block 13 are upon one side'of the track, While the insulated contactrails in advance of the train on block 13 are on the other side of the track; The retraction of the armature is of the relay 2' of block 13 causes the connection of the positive pole of the battery .9, through the armature j, conductor t, and contact m, with the insulated contact-rails g g of block 12, this circuit including no resistance such as por 4. At the same time the retraction of the armature 7c serves to connect the positive pole of the high-voltage battery 8, through armature Z. and contact Z, with the insulated contact-rails h h of block 14:. This circuit also contains no extrathrough a resistance with the insulated contact-rails two blocks in either direction. and, secondly, with the insulated contact-rails one block in either direction, this latter circuit containing no extraneous resistance, and this will be true no matter upon which block the truck is present.

The circuit arrangements of the engine-cab are indicated in Fig. 2. In this figure I have shown the wheels 20 and 21 connected by an axle 22. There is shownagrounding-contact 23 for making connection when passing over the grounded contact-rails f f. There are also shown in Fig. 2 a forward contact-shoe 24 and a backing contact-shoe 25, the contactshoe 24 being connected with switch-point 26, while the backing contact-shoe 25 is connected with switch-point 27. From the groundingcontact 23 a conductor 28 leads to the winding of the stop-relay 29, thence through the winding of the caution-relay 30, and thence through the winding of the test-relay 31 to a switch-arm 32. A local source of current, such as the battery 33, is provided for the purpose of affording current to cause the illumination of the stop-signal lamp 34, the caution-signal lamp 35, or the circuit-indicator lamp 36, as the case may be. The local circuit through the lamp 34 is controlled by the armature 37 of the relay 29, the local circuit through the lamp 35 is controlled by the armature 38 of the relay 30, and the local circuit for the lamp 36 is controlled by the armature 39 of the relay 31. The attraction of any one of these armatures by its associated relay-core causes the illumination of its associated lamp and the consequent display of the signal.

As will be hereinafter more fully understood, the exact nature of the signals displayed or actuated is not an essential feature of my invention, and electric gongs or mechanical signals may be provided in place of the electric lamps shown. The signals indicated by the illumination of these lamps may be determined by the relative location of the lamp itself or thelamp-bulbs may be variously colored. For instance, the circuit-indicator lamp may be white, the caution-signal may be produced by the illumination of an orangecolored lamp, while the bulb of the stop-signal lamp may be red to indicate danger.

I shall now describe the operation of my improved block-signaling system under various conditions which may arise in practice,

Supposing there is upon block 11 an engine moving in the direction of the arrow 41, this engine being equipped with the signaling apparatus diagrammatically illustrated in Fig. 2. If the engine is moving forward in the direction of the arrow 41, the switch 32 should be thrown so as to connect with-the contactpoint 26, connected with the forward contactshoe 24. This contact-shoe 24 is so placed upon the locomotive as to make electrical connection with the contacts g g upon the righthand side of the track upon passing over these contacts. The contacts 9 9 may be of any desirable length and of any desired number for each block. Indeed, the contacts g 9 may be of such length that for each block there is but one continuous insulated contact-rail g. It is desirable, however, that the grounded contacts ff be of the same length and similarly disposed as are the insulated contactrails g g. Thus at the time the forward contact-shoe 24 makes connection with an insulated contact-rail g the grounding-contact 23 will also make connection with a corresponding grounded contact f. Upon making electrical connection with these contacts f and g of block 11 the following circuit may be traced, it being assumed that the track ahead for at least three blocks is clear: from forward contact-shoe 24 to insulated contactrail g, through resistance 19 of block 13, armature front contact 72, low-voltage battery 0, ground G, thence to the grounded contact f opposite the insulated contact g, thence through the grounding-contact 23, conductor 28, the serially-connected relays 29, 30, and 31, switch-arm 32, and thence through contact-point 26 back to the forward contactshoe 24. It will be noticed that this circuit includes the battery 0 of relatively low voltage and also the resistance 19. Now the relays 29, 30, and 31 are dilferently wound or differently adjusted, or both, the adjustment being such that the current flowing, due to the electrical connection of the low-voltage battery 0, through aresistancep will not cause the attraction of the armatures of the relays 29 or 30, which relays control the caution and the stop signals. This current, however, is of sufficient strength to cause the attraction of the armature of the relay 31, whereby a local circuit is closed through the circuit-indicator lamp 36, the illumination of this white lamp indicating that the circuit arrangements are in proper working order.

If for any reason the low-voltage battery 0 is out of order or if the circuit connections between blocks 11 and 13 are out of order or if the circuit arrangements upon the engine itself are out of order, the relay 31 will not be energized to cause the illumination of the circuit-indicator lamp 36. The failure of this lamp to illuminate and display its signal will indicate at once to the engineer that the block system is in some respect out of order and cannot be relied upon as a signaling system. The periodic illumination of the circuit-indicator lamp, however, or if the contact-rails g and f are made continuous for each block then the continuous illumination of the circuit-indicator lamp 36, will notify the engineer that the block-signaling system is in order and may be relied upon forsignaling purposes.

If now there is a truck of any kind whatsoever upon block 13', it will be remembered that the associated relay 2' is short-circuited or shunted, whereby it is deenergized' to permit the retraction of its armatures j and is. It will be remembered, furthermore, that the retraction of these armatures for one thing disconnects the positive pole of the low-voltage battery 0 from the contacts g of block 11, but that the positive pole of the high-voltage battery s is connected, through a resistance 19, with these contacts g of block 11. Furthermore, the deenergization of the relay '5 of block 13 causes the connection of the positive pole of the high-voltage battery 8 directly with the contacts g of block 12 without the interposition of any resistance, such as p or q. Under this condition when there is a truck upon block 13 and an engine provided with the circuit arrangements shown in Fig. 2 is moving in the direction of the arrow 41 upon block 11 the following circuit may be traced: from the negative pole of the high-voltage battery 8 to the ground G, thence through the ground to the grounded contactf of block 11, through the grounding-contact 23, which is mounted upon the engine in block 11, through conductor 28, relays 29, 30, and 31, switch-arm 32, switch-point 26, forward contact-shoe 24, contact of block 11, resistance 1), armatu rej, and thence through back contact a to the positive pole of the battery .9. On account of the resistance p in this circuit the relays 29, 30, and 31 are not subjected to the full strength of current which would otherwise flow due to the pressure of the battery 8. The current, however, which flows in this case will be greater than that due to the pressure of the low-voltage battery 0, and this current is of sufficient strength to cause the actuation not only of relay 31, but of relay 30 also. The attraction of the armature of relay 31, as in the former case, causes an illumination of the circuit-indicator lamp 36 to indicate that the system is in proper operative condition, and the attraction of the armature 38 of.relay 30 causes the illumination of the caution-signal lamp 35, thereby indicating to the engineer on the train in block 11 that the track is in some way obstructed two blocks in advance. It will be remembered also that the presence of the truck on block 13 has caused adirect connection of the positive pole of the high-voltage battery 8 with the insulated contact-rails g of block 12, there being no resistance included in this circuit. When, therefore, the engine on block 11 moves onto block 12, a circuit may be traced as follows: from the negative pole of the high-voltage battery 8 to ground G, to grounded contactf of block 12, through the grounding-contact 23, conductor 28, relays 29, 30, and 31, switch-arm 32, switch-point 26, forward contact-shoe 24, insulated contact-rail g of block 12, to contact m of block 13, armature 70, which is now in its retracted position, conductor t, armature j, and contact 0* to the positive pole of the high-voltage battery .9. Current flowing over this circuit will be greater in strength than that flowing over the circuit traced when the engine was in block 11, for the reason that the extraneous resistance has been cut out of the circuit. The current flowing due to the direct pressure of the highvoltage battery 8 is of suflicient strength to cause the attraction of the armature of the relay 29 in addition to the armatures of the relays 30 and 31. The actuation of relay 29 causes theillumination of the stopsignal lamp 34. The actuation of this dangersignal at once indicates to the engineer on the train in block 12 that the track is obstructed in block 13. He may therefore bring his train to a full stop in order to avoid a collision. When the truck on block 13 has been moved ofi, the relay 6 of block 13 will again be energized to cause the attraction of the armatures j and 7?, whereby either of the circuits through the signaling-circuit in the cab of the engine on block 11 or 12 will be broken. If the truck which has been described as on block 13 is moving in the same direction as is the engine following, which has been described as on blocks 11 and 12, there will be no signal produced except the circuitindicator signal in the cab of the following engine so long as the leading engine or truckis more than three blocks in advance. When the leading engine is only two blocks in advance, the caution-signal will be actuated in the cab of the following engine, the actuation of this caution-signal being intermittent or continuous, depending upon the length of the insulated contact-rails g and the grounded contact-rails f. When the following engine approaches within one block of the leading engine, the stop-signal will be at once actuated to indicate to the following engineer that there is a train on the next block in advance. The leading engine, which is moving in the direction of the arrow 41, may, if desired, be equipped with the cab-signaling-circuit ar' rangements. In this case the forward eontact-shoe 24 will make connection with the insulated contact-rails g These contactrails g are not affected by the following engine or truck, but are affected only by a truck on a block in advance of the moving train; The leading engine therefore will in no wise be signaled, either to caution or stop by afollowing engine.

If there is on block 13 an engine moving in the direction of the arrow 42 and there is on block 11 an engine moving in the direction of the arrow 41, the signaling arrangements in the cab of the engine on block 13 will be actuated to cause the display of the caution-signal. This is for the reason, as will be at once understood, that the presence of the truck of the engine on block 11 will cause the deenergization of the associated relay whereby the relay-armatures j and is are retracted to cause the connection of the positive pole of the battery .9 of block 11 with the contacts it h, located in block 13. This connection of the positive pole of the battery 8 with the insulated contact-rails it in block 13 will include the resistance g. This resistance, as has previously been explained, is sufficient to prevent the flow of a current of sufficient strength to cause the actuation of the relay 29. The relay 30, however, located on the cab of the engine moving in the direction of the arrow 42 in block 13, will be energized to cause the attraction of its armature 88, whereupon the caution-signal will be actuated to indicate to the engineer of the train in block 13 that he is approaching a train in block 11.- At the same time, of course, the engineer of the train in block 11, which is approaching head-on, will be given the caution-signal, as previously explained. When the trains have entered adjacentblocks, the stop-signal will be displayed in both of the engine-cabs, as will be readily understood from previous explanation.

As it may frequently happen that an engine moves backward along the track-that is, with the tender first and the engine behindI have found it desirable to provide some automatic means whereby the proper contact-shoe may be brought into service and electrical connection. While it is of courseimmatcrial whether the insulated contact-rails g and it be placed within or without the main rails a and Z), it is desirable that an engine equipped with my improved signaling apparatus should make contact with one set of insulated contacts when moving in one direction and with the other set of insulated contact-rails when moving in the other direction. As a simple means of accomplishing this change in electrical connection between the contact-shoes I have illustrated inFig. 3 the reverse-lever 43 of an engine, to which may be attached the switcharm 32, as shown. The contact-points 26 and 27 may be made in the shape of segments, over which the switch-arm rides. Thus when the reverse-lever is thrown in one position to permit the forward movement of the engine the switch-arm 32 will be brought into electrical connection with the contact-point 26, connected with the forward contact-shoe 24. hen the reverse-lever is thrown to permit the engine to back, the switch-arm 32 will be thrown into electrical connection with the contact-point 27, which is connected with the backing contact-shoe 25. In this manner the engineer will be provided with the proper cabsignals whether his engine be moving forward or backward. It will of course be apparent to those skilled in the art that a great many other automatic arrangements for accomplishing this result may be used with equal advantage. It will be seen, furthermore, that various means may be employed for the purpose of charging the insulated contact-rails to various potentials, depending upon the proximity of an obstructed block. A great variety of other modifications will be apparent to those acters, except that in Fig. 4 these reference i characters are primed. The engine-cab equipment maybe the same for either modification of the invention. The track-relays z," in the modification shown in Fig. 4 are provided with but a single armature j. I have numbered the blocks in Fig. 4 as 7, 8, 9, and 10. The presence of a truck on, say, block 9 will cause the relay t" to be shunted and deenergized, whereby the associated armature 1' will be retracted to make connection with the positive pole of the high-voltage battery .9. Under normal conditions the armature ,7" makes connection with the front contact a to provide for the test-circuit. Under this normal condition the following connections may be traced: from the positive pole of the lowvoltage battery 0 of block 9 through contact at, armature j, to insulated contacts 9 g of block 8. The resistance a is connected between any desired insulated contacts in order that certain contact connections may cause caution-signals and others stop-signals. The insulated contact-rail g is more or less common to blocks 8 and 9, it being noted that the breaks between the main rails to a of different blocks are not placed opposite the break in the electrical continuity of the main rails 7) b. This overlapping of the blocks is for the purpose of preventing the presence at any time of conditions such that the proper signals would not be displayed. The connection of the armature with the contact it also serves to connect the insulated contacts it, [1/ and 7? with the positive pole of the battery 0. The contact-rail 71, is in this instance also connected with the others by an electrical circuit which includes a resistance '0. The contactrails 72/ and h are connected directly with the positive pole of the battery 0, the contact 7t being more or less common to the blocks 9 and 10. As in the case of the system illustrated in Fig. 1, the insulated contact-rails may be of any desired length, and, if desired, they may closely approach each other, so that the signals may be displayed continuously rather than intermittently,

An engine equipped with my improved signaling devices and moving in the direction of the arrow 44 upon reaching block 8 causes the closure of the following circuit: fromthe negative pole of the low-voltage battery 0 at the positive pole of the battery The 010-- sure of this circuit through the relays 29, 30, and 31 causes the actuation of' relay 31 only, as the other relays are adjusted so as not to be actuated except upon the passage of aconsiderably greater current. The actuation of the relay 31 causes the illumination of the test indicator-lamp to indicate to the engineer that the systemis in proper operative condition. In the same manner the engine upon reaching a point in block 8 such that connection is made with the insulated contact-rail g and the grounded contactf' causes an illumination of the circuit-indicator lamp. The circuit which will be closed at this pointdoes not include the resistance u and will therefore be of somewhat greater strength than that previously traced through the relays 29, 30, and 31. The relays 29 and 30 are so adjusted as not to be actuated by either of these currents, due to the pressure of the battery 0. This test-signal will be again repeated upon making connection with'contacts g and f In fact, these intermittent illuminations of the test-lamp will occur as each set of contacts is crossed so long as the block system is in proper operative condition. As I have previously explained, the insulated contacts and the grounded contacts may be of such length that the test-signal and other signals shall be continuous in their operation rather than intermittent. If now there is a truck obstructing block 9, the associated relay 7; will be deenergized, so that the associated armature will make connection with the contact 1", connected with the positive pole of the high-voltage battery 3. This will of course cause an increase in the potential of the contacts g. 9 and g When, therefore, an engine equipped with the signaling-circuits reaches block 8 and connection is made with the grounded contact f and the insulated contact 9, a circuit will be closed through the relays 29, 30, and 31, the current flowing being of sufiicient strength. due to the pressure of the battery .9, to cause the actuation of the relay 30. The presence of the resistance 16, however, will prevent the flow of sufficient current to cause the actuation of the relay 29. The engineer of the train moving in the direction of the arrow 44. will thus be informed by the illumination of the caution-signal lamp that there is an ob struction on block 9. Upon reaching the contacts g and f 2 the resistance 14 will have been cut out of the circuit, whereby sufficient current will be permitted to flow to cause the actuation of the'relay 29, thereby giving the engineer the dead-stop signal to indicate that "there is an I obstruction upon the next block in advance. 'This track arrangement, as in the case of that illustrated in Fig. 1, will operate to produce signals in the cabs of both 1 engines when the trains are approaching each other head-on. If the breaks between blocks were not staggered, as shown, it might be possible for two engines to enter the same block at the same instant without causing the proper actuation of the signals; but by staggering the breaks as shown this unusual con dition will cause the operation of the signals to warn both engineers of the danger ahead.

WVhile I have herein shown and described a preferred embodiment 01 my invention and this modification, which may be used to advantage where long blocks may be employed,

it will be apparent to those skilled in the art that many modifications may be devised all of which will come within the scope of my invention.

What [claim as new, and desire to secure by Letters Patent, is

1. In a railway block-signaling system, the combination with a series of blocks, of two signal-controlling devices, each in a separate block, and two signal-conveying paths, each 'path being adapted to convey signals to a different block, the actuation of the first signalcontrolling device serving to establish one condition in the first of said paths and another condition in the second of said paths, and the actuation ol the second signal-controlling device serving to establish the said second condition in the first of said paths.

2. In a railway block-signaling system, the combination with a series of blocks, of two signal-controlling devices, each in a separate block, two signal-conveying paths, each path being adapted to convey signals to a diflerent' block, the actuation of the first signal-controlling device serving to establish one condition in the first of said paths and another condition in the second of said paths, and the actuation of the second signal-controlling device serving to establish the said second condition in the first of said paths, and means whereby the presence of a car-truck in one of said blocks causes an actuation of the associated signal-controlling device;

3. In a railway block-signaling system, the combination with a series of blocks, of two signal-controlling devices, each in a separate block, two signal-conveying paths, each path being adapted to convey signals to a different block, the actuation of the first signal-controlling device serving to establish one condition in the first of said paths and another condition in the second of said paths, and the actuation of the second signal-controlling device serving to establish the said second con- 4. In a railway block-signaling system, the combination with a series of blocks, of two signal-controlling devices, each in a separate block, two signal-conveying paths, each path being adapted to convey signals to a different block, the actuation of the first signal-controlling device serving to establish one condition in the first of said paths and another condition in the second of said paths, and-the actuation of the second signal-controlling device serving to establish the said second condition in the first of said paths, and signaldisplaying devices adapted to be actuated to display a certain signal during the establishment of the first condition in the connected conveying-path and to display another signal during the establishment of the second condition in the connected conveying-path.

5. In a railway block-signaling system, the combination with a series of blocks, of two signal-controlling devices, each in a separate block, two signal-conveying paths, each path being adapted toconvey signals to a different block, the actuation of the first signal-controlling device serving to establish one con dition in the first of said paths and another condition in the second of said paths, and the actuation of the second signal-controlling device serving to establish the said second con dition in the first of said paths, means whereby the presence of a car-truck in one of said blocks causes an actuation of the associated signal-controlling device, and signal-displaying devices adapted to be actuated to display a certain signal during the establishment of the first condition in the connected conveying-path and to display another signal during the establishment of the second condition in the connected conveying-path.

6. In a railway block-signaling system, the combination with a series of blocks, of two signal-controlling devices, each in a separate block, two signal-conveying paths, each path being adapted to convey signals to a different block, the actuation of the first signal-controlling device serving to establish one condition in the first of said paths and another condition in the second of said paths, and the actuation of the second signal-controlling device serving to establish the second condition in the first of said paths, means whereby a defect in the track or block signal-controlling equipment of one block causes an actuation of the signal-controlling device associated with said block, and signal-displaying devices adapted to be actuated to display a certain signal during the establishment of the first condition in the connected conveying-path and to display another signal during the establishment of the second condition in the connected conveying-path.

7. In a railway block-signaling system, the combination with a series of blocks, of two electromagnetic signalcontrolling devices, each in a separate block, and two signal-conveying paths, each path being adapted to convey signals to a difierent block, said electromagnetic signal-controlling device being actuated upon the presence of a car-truck upon the associated block, or upon a defect in the blocksignal-controlling circuit, the actuation of the first signal-controlling device serving to establish one condition in the first of said paths and another condition in the second of said paths, and the actuation of the second signal-controlling device serving to establish the said second condition in the first of said paths.

8. In a railway block-signaling system, the combination with a series of blocks, of two electromagnetic signal controlling devices, each in a separate block, two signal-conveying paths, each path being adapted to convey signals to a different block, said electromagnetic signal-controlling device being actuated upon the presence of acar-truck upon the associated block, or upon a defect in the block-signalcontrolling circuit, the actuation of the first signal-controlling device serving to establish one condition in the first of said paths and another condition in the second of said paths, and the actuation of the second signal-controlling device serving to establish the said second condition in the first of said paths, and signaldisplaying devices adapted to be actuated to display a certain signal during the establishment of the first condition in the connected conveying-path and to display another signal during the establishment of the second condition in the connected conveying-path.

9. In a railway block-signaling system. the combination with a series of blocks, of two signal-controlling devices, each in a separate block, two signal-conveying paths, each path being adapted to convey signals to a different block, the actuation of the first signal-controlling-device serving to establish one. condition in the first of said paths and another condition in the second of said paths, and the actuation of the second signal-controlling device serving to establish the said second condition in the first of said paths, and a signal-displaying device mounted on a moving train adapted to be actuated to displaya certain signal during the establishment of the first condition in the conveyingpath connected with said signaldisplaying device and to display another signal during the establishment of the second condition in the connected conveying-path.

10. In a railway block-signaling system, the combination with a series of blocks, of two electromagnetic signal controlling devices, each in a separate block, each of said signalcontrolling devices being actuated upon the presence of a car-truck in the associated block, two signal-conveying paths, each path being adapted to convey signals to a difi'erent block, the actuation ofthe first signal-controlling device serving to establish one condition in the first of said paths and another condition in the second of said paths, and the actuation of the second signal-controlling device serv- IIO ing to establish the second condition in the first of said paths, and a signal-displaying device mounted on an engine-cab, adapted to be connected with the signal-conveying path aselectromagnetic signal-controlling devices,

each in a separate block, and two signal-conveying paths, each path being adapted to convey signals to a different block, the electromagnetic signal-controlling device being actuated upon the presence of a car-truck in the associated block, or upon a defect in the controlling-circuit for said electromagnetic signal-controlling device, the first electromagnetic signal-controlling device serving normally to cause the establishment of a test condition in the first of said paths, and the actuation of the first signal-controlling device serving to establish a second condition in the first of said paths and a third condition in the second of said paths, and the actuation of the second signal-controlling device serving to establish the third condition in the first of said paths.

12. In a railway block-signaling system, the combination with a series of blocks, of two electromagnetic signal controlling devices, each in a separate block, two signal-conveying paths, each path being adapted to convey signals to a different block, the electromagnetic signal-controlling device being actuated upon the presence of a car-truck in the associated block, or upon a defect in the controlling-circuit for said electromagnetic signal-controlling device, the first electromagnetic signalcontrolling device serving normally to cause the establishment of a test condition in the first of said paths, and the actuation of the first signal-controlling device serving to establish a second condition in the first of said paths and a third condition in the second of said paths, and the actuation of the second signal-controlling device serving to establish the third condition in the first of said paths, and a signal-displaying device adapted for connection with said signal-conveying paths, and adapted to display a difierent signal for each of the three conditions set up in the signalconveying paths.

' l3. Inarailway block-signaling system, the combination with a series of blocks, of two electromagnetic signal-controlling devices, each in a separate block, two signal-conveying paths, each path being adapted to convey signals to a different block, the electromagnetic signal-controlling device being actuated upon the presence of a car-truck in the associated block, or upon a defect in the controlling-circuit for said electromagnetic signal -controlling device, the first electromagnetic signalcontrolling device serving normally to cause the establishment of a test condition in the first of said paths, and the actuation of the first signal-controlling device serving to establish a second condition in the first of said paths anda third condition in the second of said paths, and the actuation of the second signalcontrolling device serving to establish the third condition in the first of said paths, and a signal-displaying device mounted on an engine-cab and adapted for connection with the signal-conveying path leading to the block in which the engine is present, and adapted to be actuated to display one signal during the establishment of the first condition in the connected conveying-path, to display a second signal during the establishment of the second condition in the connected conveying-path, and to display a third signal during the establishment of the third condition in the connected conveying-path.

14:. In a railway block-signaling system, the combination with a series of blocks, of two signal-controlling devices, each in a separate block, two signal-conveying paths, each path being adapted to convey signals to a different block in a forward direction, and two signal conveying paths, each path being adapted to convey signals to a different block in a backward direction, the actuation of the first signal-controlling device serving to establish one condition in the first path in the forward direction and in the first path in the backward direction, and another condition in the second path in the forward direction and in the second path in the backward direction, and the actuation of the second signal-controlling device serving to establish the second condition in the first path in either direction.

15. In a railway block-signaling system, the combination with a series of blocks, of two signal-controlling devices, each in a separatev block, two signal-conveying paths, each path being adapted to convey signals to a different block in a forward direction, two signal-conveying paths, each path being adapted to convey signals to a different block in a backward direction, the actuation of the first signalcontrolling device serving to establish one condition in the first path in the forward direction and in the first path in the backward direction, and another condition in the second path in the forward direction and in the second path in the backward direction, and the actuation of the second signal-controlling device serving to establish the second condition in the first path in either direction, and means whereby the presence of a car-truck in one of said blocks causes an actuation of the associated signal-controlling device.

16. In arailway blocksignaling system, the combination with a series of blocks, of two signal-controlling devices, each in a'separate block, two signal-conveying paths, each path being adapted to convey signals to a different block in a forward direction, two signal-conveying paths, each path being adapted to convey signals to a different block in a backward direction, the actuation of the first signal-controlling device serving to establish one condition in the first path in a forward direction and in the first path in the backward direction, and another condition in the second path in the forward direction and in the second path in the backward direction, and the actuation of the second signal-controlling device serving to establish the second condition in the first path in either direction, and means whereby said first signal-controlling device normally causes the establishment of a test condition different from either of the other two aforesaid conditions in the first of said paths in either direction.

17. In a railway block-signaling system, the combination with a series of blocks, of two signal-controlling devices, each in a separate block, two signal-conveying paths, each path being adapted to convey signals to a different block in a forward direction, two signal-conveying paths, each path being adapted to con vey signals to a different block in a backward direction, the actuation of the first signal-controlling device serving to establish one condition in the. first path in the forward direction and in the first path in the backward direction, and another condition in the second path in the forward direction and in the second path in the backward direction, and the actuation of the second signal-controlling device serving to establish the second condition in the first path in either direction, means whereby the presence of a car-truck in one of said blocks causes an actuation of the associated signal-controlling device, and means direction, the actuation of the first signal-controlling device serving to establish one con' dition in the first path in the forward direction and in the first path in the backward direction, and another condition in the second path in the forward direction and in the second path in the backward direction, and the actuation of the second signal-controlling de- Vice serving to establish the second condition in the first path in either direction, and a sigfoal-displaying device mounted on an enginecab, adapted to be actuated to display a certain signal during the establishment of the first condition in the connected conveyingpath, and to display another signal during the establishment of the second condition in the connected conveying-path.

19. In a railway block-signaling system, the combination with a series of blocks, of two signal-controlling devices, each in a separate block, two signal-conveying paths, each path being adapted to convey signals to adifferent block in a forward direction, two signal-conveying paths, each path being adapted to convey signals to a different block in a backward direction, the actuation of the first signal-controlling device serving to establish one condition in the first path in the forward direction and in the first path in the backward direc tion, and another condition in the second path inthe forward direction and in the second path in the backward direction, and the actuation of the second signal-controlling device serving to establish the second condition in the first path in either direction, means whereby the presence of a car-truck in one or said blocks causes an actuation of the associated signal-controlling device, and a signal-displaying device mounted on an engine-cab, adapted to be actuated to display a certain signal during the establishment of the first condition in the connected conveying-path, and to display another signal during the establishment of the second condition in the connected conveying-path.

20. In a railway block-signaling system, the combination with a series of blocks, of two signal-controlling devices, each in a separate block, two signal-conveying paths, each path being adapted to convey signals to a different block in a forward direction, two signal-conveying paths, each path being adapted to convey signals to a different block in a backward direction, the actuation of the first signal-controlling device serving toestablish one condition in the first path in the forward direction and in the first path in the backward direction, and another condition in the second path in the forward direction. and in the second path in the backward direction, and the actuation of the second signal-controlling device serving to establish the second condition in the first path in either direction, and a signal-displaying device adapted to be actuated to display a certain signal during the establishment of the first condition in the connected conveying-path and to display another signal during the establishment of the second condition in the connected conveying-path. I

21. In a railway block-signaling system, the combination with a series of blocks, of two signal-controlling devices, each in a separate block, two signal-conveying paths, each path being adapted to convey signals to a different block in a forward direction, two signal-concauses the establishment of a. test condition different from either of the other two aforeveying paths, each path being adapted to convey signals to a different block in a backward direction, the actuation of the first signal-controlling device serving to establish one condition in the first path in the forward direction and in the first path in the backward direction,

and another condition in the second path in the forward direction and in the second path in the backward direction, and the actuation of the second signal-controlling device serving to establish the second condition in the first path in either direction, means whereby 'the'presence of a car-truck in one of said blocks causes an actuation of the associated signal-controlling device, and a signal-displaying device adapted to be actuated to display a certain signal during the establishment of the first condition in the connected conveying-path and to display another signal during veying paths, each path being adapted to convey signals to a different block in a backward direction, the actuation of the first signal-controlling device serving to establish one condition in the first path in the forward direction and in the first path in the backward direction,

and another condition in the second path in the forward direction and in the second path in the backward direction, and the actuation of the second signal-controlling device serving to establish the second condition in the first path in either direction, means whereby said first signal-controlling device normally said conditions in the first of said paths in either direction, and a signal-displaying device mounted on an engine-cab, adapted for connection with the signal-conveying path leading to the block in which the engine is present, and adapted to be actuated to display a certain signal during the establishment of the first condition in the connected conveyingpath and to display another signal during the establishment of the second condition in the connected conveying-path, and adapted to display a test-signal to indicate the proper operative condition of the block-signaling system during the establishment of the said test condition in the connected conveying-path.

' 23. In a railway block-signaling system, the combination with a series of blocks, of two signalcontrolling devices, each in a separate block, two signal-conveying paths, each path being adapted to convey signals to a different block in a forward direction, two signal-conveying paths, each path being adapted to convey signals to a different block in a backward direction, the actuation of'the first signal-controlling device serving to establish-one condition in the first path in the forward direction and in the first path in the backward direction, and another condition in the second path in the forward direction and in the second path in the backward direction, and the actuation of the second signal-controlling device serving to establish the second condition in the first path in either direction, means whereby the presence of a car-truck in'one of said blocks causes an actuation of the associated signal-controlling device, and a signal-displaying device mounted on an engine-cab, adapted for connection with the signal-conveying path leading to the block in which the engine is present, and adapted to be actuated to display a certain signal during the establishment of the first condition in the connected conveyingpath and to display another signal during the establishment of the second condition in the connected conveying-path, and adapted to display a test-signal to indicate the proper operative condition of the block-signaling system during the establishment of the said test condition in the connected conveying-path.

24. In a railway block-signaling system, the combination with a series of blocks, of two signal-controlling devices, each in a separate block, two signal-conveying paths, each path being adapted to convey signals to a different block in a forward direction, two signal-conveying paths, each path being adapted to convey signals to a different block in abackward direction, the actuation of the first signal-controlling device serving to establish one condition in the first path in the forward direction and in the first path in the backward direction, and another condition in the second path in the forward direction and in the second path in the backward direction, and the actuation of the second signal-controlling device serving to establish the second condition in the first path in either direction, means whereby said firstsignal-eontrolling device normally causes the establishment of a test condition different from either of the other two aforesaid condition in the first of said paths in either direction, and a signal-displaying device adapted to be actuated to display a certain signal during the establishment of the first condition in the connected conveying-path and to display another signal during the establishment of the second condition in the connected conveying-path, and adapted to display a testsignal to indicate the proper operative condition of the block-signaling system during the establishment of the said test condition in the connected conveying-path.

25. in a railway block-signaling system, the combination with a series of blocks, of two signal-controlling devices, each in a separate block, two signal-conveying paths, each path being adapted to convey signals to a different block in a forward'direction, two signal-conveying paths, each path being adapted to convey signals to a different block in a backward direction, the actuation of the first signal-controlling device serving to establish one condition in the first path in the forward direction and in the first path in the backward direction, and another condition in the second path in the forward direction and in the second path in the backward direction, and the actuation of the second signal-controlling device serving to establish the second condition in the first path in either direction, means whereby the presence of a car-truck in one of said blocks causes an actuation of the associated signalestablishment of the first condition in the connected conveying-path and to display another signal during the establishment of the second condition in the connected conveying-path, and adapted to display a test signal to indicate the proper operative condition of the block-signaling system during the establishment of the said test condition in the connected conveying-path.

26. In a railway block-signaling system, the combination with a series of blocks, of two electromagnetic signal-controlling devices, each in a separate block, two signal-conveying paths, each path being adapted to convey signals to a diflierent block in a forward direction, and two signal-conveying paths, each path being adapted to convey signals to adifferent block in a backward direction, the actuation of the first signal-controlling device serving to establish one condition in the first path in the forward direction and in the first path in the backward direction, and another condition in the second path in the forward direction and in the second path in the backward direction, and the actuation of the second signal-controlling device serving to establish the second condition in the first path in either direction.

27. In a railway block-signaling system, the

combination with a series of blocks, of two the forward direction and in the first path in the backward direction, and an other condition 1n the second path in the forward direction and in the second-path in the backward direction, and the actuation of the second signal-.

controlling device serving to establish the second condition in the first path in either direction, and means whereby the first of said signal-controlling devices when in its normal condition causes the establishment of a test condition in the first of said paths in either direction.

28. Inarailway block-signaling system, the combination with a series of blocks, of two electromagnetic signal controlling devices, each in a separate block, two signal-conveying paths, each path being adapted to convey signals to a different block in a forward direction, two signal-conveying paths, each path being adapted to convey signals to a different block in a backward direction, the actuation of the first signal-controlling device serving to establish one condition in the first path in the forward direction and in the first path in the backward direction, and another condition in the second path in the forward direction and in the second path in the backward direction, and the actuation of the second signal-controlling device serving to establish the second condition in the first path in either direction, and means whereby the presence of a car-truck in one of said blocks or a defect in the controlling-circuit for said electromagnetic signal-controlling device causes an actuation of the associated signal-controlling, de-

vice.

29. In a railway block-signaling system, the combination with a series of blocks, of two electromagnetic signal-controlling devices, each in aseparate block, two signal-conveying paths, each path being adapted to convey signals to a different block in a forward direction, two signal-conveying paths, each path being adapted to convey signals to a different block in a backward direction, the actuation of the first signal-controlling device serving to establish one condition in the first path in the forward direction and in the first path in the backward direction, and another condition in the second path in the forward direction and in the second path in the backward direction, and the actuation of the second signalcontrolling device serving to establish the second condition in the first path in either direction, means whereby the first of said signal-controlling devices when in its normal condition causes the establishment of a test condition in the first of said paths in either direction, and means whereby the presence of a car-truck in one of said blocks or a defect in the controlling-circuit for said electromagnetic signal-controlling device causes an actuation of the associated signalcontrolling device.

30. In a railway block-signaling system, the combination with a series of blocks, of two electromagnetic signal controlling devices, each in a separate block, two signal-conveying paths, each path being adapted to convey signals to a different block in a forward direction,

two signal-conveying paths, each'path being adapted to convey signals to a different block in a backward direction, the actuation of the first signal-controlling device serving to establish one condition in the first path in the forward direction and in the first path in the backward direction, and another condition in the second path in the forward direction and in the second path in the backward direction, and the actuation of the second signal-controlling device serving to establish the second condition in the first path in either direction,

and a signal-displaying device adapted to be v actuated to display a certain signal during the establishment of the first condition in the connected conveying-path and to display another signal during the establishment of the second condition in the connected conveying-path.

31. In a railway block-signaling system, the combination with a series of blocks, of two electromagnetic signal controlling devices, each in a separate block, two signal-conveying paths, each path being adapted to convey signals to a different block in a forward direction, two signal-conveying paths, each path being adapted to convey signals to a different block in a backward direction, the actuation of the first slgnal-controllmg device serving to es tablish one condition in the first path in the forward direction and in the first path in the backward direction, and another condition in the second path in the forward direction and in the second path in the backward direction, and the actuation of the second signal-controlling device serving to establish the second condition in thefirst path in either direction, means whereby the presence of a car-truck in one of said blocks or a defect in the controlling-circuit for said electromagnetic signalcontrolling device causes an actuation of the associated signal-controlling device, and a signal-displaying device adapted to be actuated to display a certain signal during the establishment of the first condition in the connected conveying-path and to display another signal during the establishment of the second condition in the connected conveying-path.

32. In a railway block-signaling system, the combination with a series of blocks, of two electromagnetic signalcontrolling devices, each in a separate block, two signal-conveying paths, each path being adapted to convey signals to a different block in a forward direction, two signal-conveying paths, each path being adapted to convey signals to a different block in a backward direction, the actuation of the first signal-controlling device serving to establish one condition in the first path in the forward direction and in the first path in the backward direction, and another condition in the second path in the forward direction and in the second path in the backward direction, and the actuation of the second signal-controlling device serving to establish the second condition in the first path in either direction,

means whereby the first of said signal-controlling devices when in 1ts normal condition causes the establishment of a test condition in the first of said paths in either direction, and a signal-displaying device mounted on an engine-cab and adapted for connection with the signal-conveying path leading to the block. in which the engine is present, saidsignal-displaying device being adapted for actuation to display a caution-signal in the engine-cab during the establishment of the first condition in the connected conveying-path, and to'display another or stop signal upon the establishment of the second condition in the connected conveying-path, and adapted to display a test signal during the establishment of the test condition in the connected conveying-path.

38. In a railway block-signaling system, the combination with a series of blocks, of two electromagnetic signal controlling device s, each in a separate block, two signal-conveying paths, each path being adapted to convey signals to a difi'erent block in a forward direction, two signal-conveying paths, each path being adapted to convey signals to a different block in a backward direction, the actuation of the first signal-controlling device serving to establish one condition in the first path in the forward direction and in the first path in the backward direction, and another condition in the second path in the forward direction and in the second path in the backward direction, and the actuation of the second signal-controlling device serving to establish the second condition in the first path in either direction, means whereby the first of said signal-controlling devices when in its normal condition causes the establishment of a test-circuit in the first of said paths in either direction, means whereby the presence of a car-truck in one of 'saidvblocks or a defect in the controlling-circuit for said electromagnetic signal-controlling device causes an actuation of the associated signal-controlling device, and a signaldisplaying device mounted on an engine-cab and adapted for connection with the signalconveying path leading to the block in which the engine is present, said signal-displaying device being adapted for actuation to display a caution-signal in the engine-cab during the establishment of the first condition in the connected conveying-path, and to display another or stop signal upon the establishment of the second condition in the connected conveyingpath, and adapted to displaya test-signal during the establishment of the test condition in the connected conveying-path.

84L. In arailway block-signaling system, the combination with a series of blocks, of two electromagnetic signal-controlling devices,

each in a separate block, two, signal-conveying paths, each path being adapted to convey signals to a different block in a forward direction, two signal-conveying paths, each path being adapted to convey signals to a different block in a backward direction, the actuation of the first signal-controlling device serving to establish one condition in the first path in the forward direction and in the first path in the backward direction, and another condition in the second path in the forward direction and in the second path in the backward direction, and the actuation of the second signal-controlling device serving to establish the second condition in the first path in either direction, means whereby the first of said signal-controlling devices when in its normal condition causes the establishment of a test condition in the first of said paths in either direction, and signal-displaying mechanism adapted for connection with each of said conveyingpaths, said signal-displaying mechanism being adapted to cause the display of a-caution-signal during the establishment of said first condition in the connected conveying-path, and to cause the display of a stop-signal during the establishment of the second condition in the connected conveying-path, and to cause the display of a test-signal during the establishment of the test condition in the connected conveying-path.

35. In a railway block-signaling system, the combination with a series of blocks, of two electromagnetic signal controlling devices, each in a separate block, two signal-conveying paths, each path being adapted to convey signals to a different block in a forward direction, two signal-conveying paths, each path being adapted to convey signals to a difierent block in a backward direction, the actuation of the first signal-controlling device serving to establish one condition in the first path in the forward direction and in the first path in the backward direction, and another condition in the second path in the forward direction and in the second path in the backward direction, and the actuation of the second signal-controlling device serving to establish the second condition in the first path in either direction, means whereby the first of said signal-controlling devices when in its normal condition causes the establishment of a test condition in the first of said paths in either direction, means whereby the presence of a car-truck in one of said blocks or a defect in the controlling-circuit for said electromagnetic signalcontrolling device causes an actuation of the associated signal-controlling device, and signal-displaying mechanism adapted for connection with each of said conveying-paths, said signal-displaying mechanism being adapted to cause the display of a caution-signal during the establishment of said first condition in the connected conveyingpath, and to cause the display of a stop-signal during the establishment of the second condition in the connected conveying-path, and to cause the display of a test-signal during the establishment of the test condition in the connected conveying-path.

36. In a railway block-signaling system, the combination with a series of blocks, of an electromagnetic signal-controlling device for one of said blocks, said signal-controlling device being adapted for actuation during the presence of a car in its associated block, conductors leading from said signal-controlling device to two different blocks in the same direction, electromagnetic signal-displaying mechanism adapted for electrical connection with said conductors, means whereby said signal-controlling device normally permits the flow of only a certain limited current through the conductor connected with the signal-displaying device located in the farther block, and means whereby the signal-controlling device when actuated permits the flow of an increased current through said conductor.

37. Inarailway block-signalingsystem, the combination with a series of blocks, of an electromagnetic signal-controlling device for one of said blocks, said signal-controlling device being adapted for actuation during the presence of a car in its associated block, conductors leading from said signal-controlling device to two different blocks in the same direction, electromagnetic signal-displaying mechanism adapted for electrical connection with said conductors, means whereby said signal-controlling device normally permits the 5 combination with a series of blocks, of an electromagnetic signal-controlling device for each of said blocks, each of said signal-controlling devices being adapted for actuation due to the presence of a car-truck in its associated block, conductors leading from each of said signalcontrolling devices to two different blocks in the same direction and to two other blocksin the opposite direction, electromagnetic signaldisplaying mechanism adapted for electrical connection with said conductors, means whereby said signal -controlling device normally permits the flow of only a certain limited current through the conductors connected with the signaY-displaying devices located in the farther blocks, and means whereby the signal-controlling device when actuated permits the flow of an increased current through said conductors.

39. in arailway block-signaling system, the combination with a series of blocks, of an electromagnetic signal-controlling device for each of said blocks, each of said signal-controlling IIO IIS

a the farther blocks, means whereby the signal-controlling device when actuated permits the flow of an increased current through said conductors, and means whereby the actuation of said signal-controlling device permits the flow of a still greater current through the conductors connected with the signal-displaying device located in the nearer block. I

40. In a railway block-signaling system, the combination with a series of blocks, of an electromagnetic signal-controlling device for one of, said blocks, said signal-controlling device being adapted for actuation due to the presenceof a car-truck in its associated block, conductors leading from said signal-controllingdevice to two different blocks in the same direction, an electromagnetic signal-displaying mechanism adapted for electrical connection with said conductors, means whereby said signal-controlling device normally permits the flow of a current of certain character through the conductor connected with the signal-displaying device located in the farther block, and means whereby the signal-controlling device when actuated permits the flow of a current of different character through said conductor.

&1. In a railway block-signaling system, the combination with a series of blocks, of an electromagnetic signal-controlling device for one of said blocks, said signal-controlling device being adapted for actuation due to the presence of a car-truck in its associated block, conductors leading vfrom said signal-controlling device to two different blocks in the same direction, an electromagnetic signal-displaying mechanism adapted for electrical connection with said conductors, means whereby said signal-controlling device normally permits the fiow of a current of certain character through the conductor connected with the signal-displaying device located in the farther block, means whereby the signal-controlling device when actuated permits the flow of a current of different character through said'conductor, and means whereby the signal-controlling device when actuated permits the flow of a current of still another character through the conductor connected with a signal-displaying device located in the nearer block.

42. Inarailway block-signaling system, the combination with a series of blocks, of an electromagnetic signal-controlling device for one of said blocks, said signal-controlling de-' vice being adapted for actuation during the presence of acar-truck in its associated block, conductors leading from said signal-control,- ling device to two different blocks in the same direction, a plurality of relays adapted for inclusion in circuit with said conductors, said relays being adjusted so as to be actuated upon the passage of currents of different strengths, means whereby said signal-controlling device normally permits the flow of only a certain limited current through the conductor connected with said relays located in the farther block, and means whereby the signalcontrolling device when actuated permits the flow of an increased current through said conductor.

43. In a railway block-signaling system, the

a certain limited current through the conductor connected with said relays located in the farther block, means whereby the signal-controlling device when actuated permits the flow of an increased current through said conductor, and means whereby the actuation of said signal-controlling device permits the flow of a still greater current through the conductor connected with the relays located in the nearer block. v

4.4. In a railway block-signaling system, the combination with suitable fixed contacts adjacent to the main rails, of contact-shoes carried uponamovingtrain and adapted for electrical connection with said fixed contacts, electromagnetic means on said moving train adapted to be actuated to displayacertain signal during the passage of a current of one strength from one source, and to display another signal during the passage of a current of another strength from another source, and means adapted to control the circuits from said sources to said electromagnetic means through said contacts.

45. In a railway block-signaling system, the combination with suitable fixed contacts adjacent to the main rails, of contact-shoes carried upon a moving train and adapted for electrical connection with said fixed contacts, electromagnetic means on said moving train adapted to be actuated to display a certain signal during the passage of a current of one strength from one source, and to display another signal during the passage of a current of another strength from another source, and means governed by the presence or absence of a cartruck in an adjacent block adapted to control the circuits from said sources to said electromagnetic means through said contacts.

46. In a railway block-signaling system, the combination with suitable fixed contacts adjacent to the main rails, of contact-shoes carried upon an engine and adapted for electrical connection with said fixed contacts, electromagnetic signal-displaying means carried in the engine-cab adapted to be actuated to display a certain test-signal during the passage of a current of a certain strength from one source, to display a caution-signal during the passage of a current of different strength from another source, and to display a stop-signal during the passage of a current of still a third strength from one of said sources, and means governed by the presence or absence of a cartruck in some other block adapted to control the circuits from said sources to said electromagnetic means through said contacts.

47. In a railway block-signaling system, the combination with suitable fixed contacts adja cent to the main rails, of contact-shoes carried upon a moving train and adapted for electrical connection with said fixed contacts, electromagnetic signal-displaying means carried in the engine-cab adapted to be actuated to display a certain test-signal during the passage of a current of a certain strength from one source, to display a caution-signal during the passage of a current of greater strength from another source, and to display a stopsignal during the passage of a current of a third and still greater strength from one of said sources, and means governed by the presence or absence of a car-truck in some other block adapted to control the circuits from said sources to said electromagnetic means through said contacts.

48. In a railway block-signaling system, the combination with suitable fixed contacts adjacent to the main rails, of contact-shoes carried upon an engine and adapted for electrical connection with said fixed contacts, electromagnetic signal-displaying means carried in the engine-cab adapted to be actuated to display a certain test-signal during the passage of a current of a certain strength from one source, to display a caution-signal during the passage of a current of different strength from another source, and to display a stop-signal during the passage of a current of still a third strength from one of said sources, and means adapted to control the circuits from said sources to said electromagnetic means through said contacts.

49. In a railway block-signaling system, the combination with suitable fixed contacts adjacent to the main rails, of contact-shoes carried upon a moving train and adapted for electrical connection with said fixed contacts, electromagnetic signal-displaying means carried inthe engine-cab adapted to be actuated to display a certain test-signal during the passage of a current of a certain strength from one source, to display a caution-signal during the passage of a current of greater strength from another source, and to display a stopsignal during the passage of a current of a third and still greater strength from one of said sources, and means adapted to control the circuits from said sources to said electromagnetic means through said contacts.

50. In a railway block-signaling system, the combination with a series of blocks, of a signalcontrolling relay for each of said blocks, said relay being serially included in circuit with the two main rails and the source of current in such a way that the presence of a car-truck on the associated block shunts the relay to cause its partial deenergization and the retraction of its armature, difierent-character current sources associated with each relay, one signal-circuit connected through one of said sources when the relay is active, a signal in said circuit responsive to current from said source, a second signal-circuit which is open when said relay is active but closed through the second source when the relay is inert, a signal in said second circuit responsive to current from said second source, a third signalcircuit which is also open when the relay is active but closed through the second source when the relay is inert, and a signal in said third circuit responsive only to said.second source.

51. In arailway block-signaling system, the combination with a series of blocks, of a signal-controlling relay for each of said blocks, said relay being serially included in circuit with the two main rails and the source of current in such a way that the presence of a cartruck on the associated block shunts the relay to cause its partial deenergization and the retraction of its armature, a conductor leading from said relay in any one block to an insulated contact in some other block, a source of current of certain pressure normally connected with said conductor, and means whereby the actuation of said relay causes the connection of a source of current of increased pressure with said conductor.

52. In arailway block-signaling system, the combination with a series of blocks, of a signal-controlling relay for each of said blocks, said relay being serially included in circuit with the two main rails and the source of current in such a way that the presence of a cartruck on the associated block shunts the relay to cause its partial deenergization and the retraction of its armature, a conductor leading from said relay in any one block to an insulated contact in the second block distant, a source of current of certain pressure normally connected with said conductor, means whereby the actuation of said relay causes the connection of a source of current of increased IIO pressure with said conductor, a resistance included in said conductor between said sources of current and said insulated contact, and means where by the actuation of a relay in one block connects the insulated contact in the ad.- acent block directly with a source of current having a pressure substantially equal to that of the second aforementioned source of current.

53. Ina railway block-signaling system, the combination with a series of blocks, of a signal-controlling relay for each of said blocks, said relay being serially included in circuit with the two main rails and the source of current in such a way that the presence of a cartruck on the associated block shunts the relay to cause its partial deenergization and the retraction of its armature, a conductor leading from said relay in any one block to an insulated contact in the second block distant, a source of current of certain pressure normally connected with said conductor, means whereby the actuation of said relay causes the connection of a source of current of increased pressure with said conductor, a resistance included in said conductor between said sources of current and said insulated contact, means whereby the actuation of a relay in one block connects the insulated contact in the adjacent block directly with a source of current having a pressure substantially equal to that of the second aforementioned source of current, electromagnetic signal-displaying means carried in the engine-cab and adapted for electrical connection with said insulated contact, said signal-displaying means being adapted to display a certain test-signal during the passage of a current due to thepressure of said low-pressure source of current and said resistances in circuit, to display a caution-signal during the passage of a current due to the pressure of said source of current of greater pressure when said resistance is in circuit, and to display a stop-signal during the passage of a current due to the pressure of said source of current of greater pressure when said resistance is cut out of circuit.

54:. In a railway block-signaling system, the combination with suitable fixed contacts adjacent to the main rails, of contact-shoes carried upon a moving train adapted for electrical connection with said fixed contacts, electromagnetic means on said moving train adapted to be actuated to display a certain signal during the passage of a current of one character from one source and to display another signal during the passage of a current of another character from another source, and means connected with the main rails adapted to control the circuits from said sources to said electromagnetic means.

55. In a railway block-signaling system, the combination with suitable fixed contacts associated with the main rail, of contact-shoes carried upon a moving train and adapted for electrical connection with said fixed contacts, electromagnetic means on said moving train adapted to be actuated to display a certain signal during the passage of the current of one character from one source and to display another signal during the passage of a current of another character from another source, and electromagnetic means connected with the rails adapted to control the circuits from said sources to said electromagnetic means.

56. In a railway block-signaling system, the combination with a series of blocks, of a signal-controlling relay for each of said blocks, said relay being serially included in circuit with the two main rails of the block and a source of current in such a way that the presence of a car-truck on the associated block shunts the relay to cause its partial denergization and the retraction of its armature, a conductor leading from the armature of said relay to a series of fixed contacts associated with another block, a source of current of onestrength normally connecting with said conductor through said relay armature, a second source of current of greater strength adapted for connection with said conductor when said armature is retracted, the other terminal of both said sources being connected with ground, grounded contacts associated with said other fixed contacts, a signaling-circuit on a moving train connected with contact-shoes for successively engaging said fixed contacts and the corresponding grounded contacts, a sensitive relay included serially in said signaling-circuit and adapted to be actuated alone when said contact-shoes engage the fixed and grounded contacts of one block and when the controlling-relay is active, a second relay in said signaling-circuit, contact of said shoes with said fixed and grounded contacts when said main controlling-relay is inert and said second source is connected with said conductor causing actuation of said second and said first relays in said signaling-circuit, and connection of said contactshoes with the fixed and grounded contacts of a succeeding block when said main relay is inert causing actuation of said first and second relays of the signal-circuit and also of the third relay of said circuit.

In witness whereof I hereunto subscribe my name this 27th day of August, A. D. 1903.

HARRY M. (JOULTER. 

